Rotary device for removing weeds from joints in a paved area

ABSTRACT

Rotary device from removing weeds from joints in a paved area, comprising an elongate frame ( 22 ) which is provided with a handle ( 23 ), a drive unit ( 24 ) mounted on the frame ( 22 ), a brush element ( 25 ) which is connected to the drive unit ( 24 ) in such a manner that it can be driven in rotation about an axis of rotation which extends substantially in a direction which is transverse with respect to the frame ( 22 ), and a guide wheel ( 28 ) coupled to the frame ( 22 ), the guide wheel ( 28 ) and the brush element ( 25 ) being provided on either side of the bottom end of the frame ( 22 ). The distance (x) between the guide wheel ( 28 ) and a centre axis of the frame ( 22 ) is at least double the distance (y) between the brush element ( 25 ) and the centre axis of the frame ( 22 ).

The invention relates to a rotary device for removing weeds from joints in a paved area in accordance with the preamble of claim 1.

The professional removal of weeds from joints of a paved area involves the use of heavy steerable machines which are provided with one or more rotating cup-like steel brushes with vertical axes of rotation. On account of their size and cost, machines of this type are not suitable for home use.

Individuals generally remove weeds from joints in paved areas around the house and in the garden manually, using a scraper or blade, optionally attached to a shank with a handle. This is heavy, time-consuming and exhausting work, and the results often leave something to be desired. Therefore, use is often also made of weedkillers, which is environmentally unfriendly.

A device in accordance with the preamble of claim 1 is known from DE-U 90 02 359, which shows a weed-removing device having a shank provided with a handle and, at its bottom end, a transverse rod which at one end is provided with a support wheel and at the other end is provided with a wire brush. By means of a distributor belt, the wire brush is driven by an electric motor located a certain distance above the transverse rod.

A drawback of this known weed-removing device is that it is relatively difficult to handle. In particular its lateral stability leaves something to be desired, the device having the tendency to veer sideways, making it difficult to correctly align the wire brush above the joint which is to be cleared. Furthermore, a relatively high compressive force has to be exerted on the shank in order for the weeds to be successfully removed from the joints.

Another weed removing device is known from DE-U 90 00 712, which in FIG. 3 discloses an embodiment having a shank provided with a handle and, at its bottom end, a large support wheel at one side of the shank and a relatively small wire brush at the other side of the shank. The wire brush is driven by a pneumatic drive by means of a distributor belt, which pneumatic drive is positioned somewhat above the middle of the shank at the side of the support wheel.

A drawback of this known weed removing device is that it is also relatively difficult to handle. In particular it is difficult to keep the wire brush correctly aligned above the joint which is to be cleared. Furthermore, a relatively high steering force and compressive force needs to be exerted on the shank in order to keep a proper alignment and brushing force respectively.

The object of the present invention is to at least partially overcome the abovementioned drawbacks and/or to create a usable alternative. More particularly, it is an object of the invention to provide a simple device which allows weeds to be removed in an environmentally friendly, more comfortable way as well as quickly and efficiently using a manually operable device which makes use of a simple rotating brush element mounted on a drive unit.

This object is achieved by a rotary device according to claim 1. The rotary device comprises an elongate frame which is provided with a handle and on which is mounted a drive unit, a brush element which is driven by the drive unit, and a guide wheel located at a distance from the brush element. The guide wheel is in this case positioned such that the distance between the centre of the guide wheel and the centre of the frame is at least double the distance between the centre of the frame and the centre of the brush element. The drive unit is provided in the vicinity of the bottom end of the frame. This arrangement means that a user advantageously has to exert less force on the frame, and also it is easier to keep the brush element manoeuvred into the joint which is to be cleared. This considerably improves the ease of use as well as the results which can be achieved with the rotary device.

In a particular embodiment, the drive unit is arranged in such a manner that its centre of gravity is located closer to the brush element than to the guide wheel, more particularly more than twice as close. This advantageously ensures that the weight of the drive unit is substantially supported by the brush element and only to a slight extent by the guide wheel. As a result, the brush element presses on the paving joint with maximum pressure derived from the weight of the drive unit and the weight of the frame. Consequently, a user may exert less compressive force on the frame.

Further preferred embodiments are defined in the subclaims.

The invention will be explained in more detail with reference to exemplary embodiments in the appended drawing, in which:

FIG. 1 shows a perspective view of an embodiment of the rotary device, in which the drive unit and the brush element are diagrammatically indicated by dashed lines;

FIG. 2 shows a front view of the device in FIG. 1, illustrating the drive unit and the brush element in full;

FIG. 3 shows a person removing weeds from joints using the device shown in FIG. 1;

FIG. 4 shows a perspective view of a preferred embodiment;

FIG. 5 shows a partial view of FIG. 4 during use; and

FIG. 6 shows a partially cut-away, diagrammatic front view of FIG. 4.

In FIGS. 1 and 2, the rotary device according to the invention comprises a machine clamp 1, which clamp is provided with a wing nut 2 and in which clamp 1 a handheld drill 12 or similar feature can be fixed using the wing nut 2. A standard steel brush with axis 13 is fixed in the drill head 12 b of the machine 12. A support frame 3 with a small wheel 4 for supporting the machine 12 is fixedly connected to the clamp 1. A shank 5 with handle 10, which may be of adjustable length, is also fixedly connected to the clamp 1. At its underside, close to the attachment to the machine clamp 1, the shank 5 is provided with a bracket 8 with wing bolt 9 for securing a guard 6 around the rotating brush 13, to which end the guard 6 is provided with an arm 7 which can be pushed so that it fits into the bracket 8 and fixed in place using the wing bolt 9. The guard 6 is provided with a flexible mud flap 6 b and with an arrow 6 a. The guard 6 is fixed into the bracket 8 using the arm 7 in such a manner that the arrow 6 a lies precisely in the plane of the rotating brush 13 in order to indicate the position of the brush 13 with respect to the joints V in the paved area 8 from which weeds W are to be removed.

FIGS. 1 and 2 work on the basis that a cordless drill with a chest will be clamped into the machine clamp 1.

FIG. 3 shows how it is possible to remove weeds from joints using the appliance provided with an electrically driven handheld drill with a power cord. In this case, the rotating steel brush of the appliance rests on the ground at the location of the joint which is to be cleaned. The support frame 3 with its small wheel 4 supports the machine so that the operator can relax when holding the handle and does not have to exert any torque thereon. FIG. 3 shows the situation in which the device is being pushed forward along the paved area. In practice, however, it has been found that the best results are obtained if the device is pulled backwards.

The machine can be switched on and off by means of a Bowden cable 11 with a pulling grip 11 a at the handle 10 and loop 11 b around the handle of the machine 12 at the location of the operating switch 12 a, as a result of which the casing 11 will depress the switch 12 a when the cable 11 is pulled by means of the pull grip 11 a.

The machine clamp may also be provided with a socket-headed clamping bolt instead of a stud with wing nut. In the case of an electric drill, the handle may be provided with an electrical switch for switching the machine on and off, or it is possible to enable the machine to be switched on and off using a system of mechanical rods which can be actuated from the handle instead of a Bowden cable.

As can be seen clearly from the figures, according to the inventive idea the distance between the small wheel 4 and the shank 5 is at least double the distance between the steel brush 13 and the shank 5, and more particularly is more than triple this distance.

Furthermore, the machine 12 is provided at the bottom end of the shank 5 and its output drive shaft lies in line with the axis of rotation of the steel brush 13.

In FIGS. 4-6, the rotary device overall is denoted by reference numeral 20. The device 20 comprises an elongate frame which comprises a shank 22 of adjustable length. At its free end, the shank is provided with a handgrip 23. In the vicinity of the bottom end of the shank 22 there is a drive unit, which in this case is formed by an electric motor 24. An electric cable extends from the electric motor 24 through a cavity in the shank 22 to a switch in the handgrip 23. The output drive shaft of the electric motor 24 is positioned transversely with respect to the axis of rotation of a brush element 25, the output drive shaft ending at the axis of rotation of the brush element 25 and driving the latter by means of a right-angled geared transmission. Furthermore, the electric motor 24 is positioned substantially parallel to the shank 22, with its output drive shaft extending at the axis of the shank 22, as seen in the transverse direction of the device.

A transverse rod 27 with a small guide wheel 28 at one end is secured to the shank 22. In this case too, in accordance with the invention the distance x between the small guide wheel 22 and the centre axis of the shank 22 is more than double the distance y between the brush element 25 and the axis of the shank 22. The distance x is in this case preferably greater than 10 centimetres. The distance y is in this case preferably less than 5 centimetres. The distances x and y added together amount to at least 15 centimetres, in order to make the device 20 sufficiently stable.

On account of the vertical arrangement of the electric motor 24 at the axis of the shank 22, together with the abovementioned distance ratio x-y, the centre of gravity z of the electric motor 24 is located closer to the brush element 25 than the small guide wheel 28. More particularly, with regard to the centre of gravity, it is also the case that the distance between this centre of gravity and the small guide wheel 28 is at least double the distance between the brush element 25 and the centre of gravity of the electric motor 24.

The diameter of the small guide wheel 28 is smaller than the diameter of the brush element 25, and more particularly is less than three quarters thereof.

A safety guard 30, which extends over more than half the outer circumference of the brush element 25, is provided around the brush element 25. A rubber mud flap 31 is provided at the rear side. This provides good protection from dirt thrown up by the brush element 25, which otherwise can hit the face or eyes or clothing. In addition, the safety guard 30 has the advantage that if an accident happens and the shank 22 of the rotating device 20 falls to the ground, the device does not tend to move. This is because in this case it is not the brush element 25 which lies on the ground, but rather the safety guard 30 which hits the ground as a result of the device falling over, so that the rotating brush element 25 is lifted off the ground. The guard 30 preferably also extends along part of the top end of the brush element 25, so that the dirt also cannot fly out in that direction.

The appliance according to the invention is not restricted to the exemplary embodiment shown in the drawings and described above. Numerous variations can be made within the scope of the invention. For example, it is possible to use other types of drive units, optionally with an internal power source. In addition to a frame in shank form, it is also possible to use other types of elongate frames, for example comprising two rods located next to one another. The brush element used may be a standard commercially available steel brush. Other types of brush element are also possible, for example brush elements made from a plastic material, for particular applications. Furthermore, the device according to the invention can also be used in other situations or applications.

Thus an environmentally friendly rotary device is provided which is inexpensive to produce, successfully follows a joint which is to be cleared without excessively high forces having to be exerted on it and provides good results with regard to the removal of weeds. 

1-12. (canceled)
 13. Rotary device for removing weeds from joints in a paved area, comprising: an elongate frame which is provided with a handle; a drive unit mounted on the frame; a brush element which is connected to the drive unit in such a manner that it can be driven in rotation about an axis of rotation which extends substantially in a direction which is transverse with respect to the frame; and a guide wheel coupled to the frame, the guide wheel and the brush element being provided on either side of the bottom end of the frame, wherein the distance (x) between the guide wheel and a centre axis of the frame is at least double the distance (y) between the brush element and the centre axis of the frame.
 14. Rotary device according to claim 13, wherein the centre of gravity (z) of the drive unit is positioned closer to the brush element than to the guide wheel.
 15. Rotary device according to claim 14, wherein the distance between the guide wheel and the centre of gravity (z) of the drive unit is at least double the distance between the brush element and the centre of gravity (z) of the drive unit.
 16. Rotary device according to claim 13, wherein the distance (x) between the guide wheel and the centre axis of the frame is greater than 10 centimetres.
 17. Rotary device according to one claim 13, wherein the distance (y) between the brush element and the centre axis of the frame is less than 5 centimetres.
 18. Rotary device according to one claim 13, wherein the output drive shaft of the drive unit is positioned substantially at right angles to the axis of rotation of the brush element.
 19. Rotary device according to claim 18, wherein the output drive shaft of the drive unit, as seen in the transverse direction, extends substantially at the centre axis of the frame.
 20. Rotary device according to claim 13, further comprising a safety guard which is provided around part of the brush element, which safety guard extends over more than half the outer circumference of the brush element.
 21. Rotary device according to claim 20, wherein the safety guard is provided, on its rear-facing side, with a mud flap.
 22. Rotary device according to claim 13, wherein the frame is of adjustable length.
 23. Rotary device according to claim 13, wherein the distance (x+y) between the guide wheel and the brush element is greater than 15 centimetres.
 24. Rotary device according to claim 13, wherein the drive unit is provided in the vicinity of the bottom end of the frame, and in particular has its output drive shaft ending at the axis of rotation of the brush element. 